arch, mm: replace for_each_memblock() with for_each_mem_pfn_range()

There are several occurrences of the following pattern:

	for_each_memblock(memory, reg) {
		start_pfn = memblock_region_memory_base_pfn(reg);
		end_pfn = memblock_region_memory_end_pfn(reg);

		/* do something with start_pfn and end_pfn */
	}

Rather than iterate over all memblock.memory regions and each time query
for their start and end PFNs, use for_each_mem_pfn_range() iterator to get
simpler and clearer code.

Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Baoquan He <bhe@redhat.com>
Acked-by: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>	[.clang-format]
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Daniel Axtens <dja@axtens.net>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Emil Renner Berthing <kernel@esmil.dk>
Cc: Hari Bathini <hbathini@linux.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Stafford Horne <shorne@gmail.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will@kernel.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Link: https://lkml.kernel.org/r/20200818151634.14343-12-rppt@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

3 files changed, 16 insertions, 17 deletions

diff --git a/arch/powerpc/kernel/fadump.c b/arch/powerpc/kernel/fadump.c
index 10ebb4bf71ad..e469b150be21 100644
--- a/arch/powerpc/kernel/fadump.c
+++ b/arch/powerpc/kernel/fadump.c
@@ -1242,14 +1242,15 @@ static void fadump_free_reserved_memory(unsigned long start_pfn,
  */
 static void fadump_release_reserved_area(u64 start, u64 end)
 {
-	u64 tstart, tend, spfn, epfn;
-	struct memblock_region *reg;
+	u64 tstart, tend, spfn, epfn, reg_spfn, reg_epfn, i;
 
 	spfn = PHYS_PFN(start);
 	epfn = PHYS_PFN(end);
-	for_each_memblock(memory, reg) {
-		tstart = max_t(u64, spfn, memblock_region_memory_base_pfn(reg));
-		tend   = min_t(u64, epfn, memblock_region_memory_end_pfn(reg));
+
+	for_each_mem_pfn_range(i, MAX_NUMNODES, &reg_spfn, &reg_epfn, NULL) {
+		tstart = max_t(u64, spfn, reg_spfn);
+		tend   = min_t(u64, epfn, reg_epfn);
+
 		if (tstart < tend) {
 			fadump_free_reserved_memory(tstart, tend);
 
diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c
index 42e25874f5a8..80df329f180e 100644
--- a/arch/powerpc/mm/mem.c
+++ b/arch/powerpc/mm/mem.c
@@ -184,15 +184,16 @@ void __init initmem_init(void)
 /* mark pages that don't exist as nosave */
 static int __init mark_nonram_nosave(void)
 {
-	struct memblock_region *reg, *prev = NULL;
+	unsigned long spfn, epfn, prev = 0;
+	int i;
 
-	for_each_memblock(memory, reg) {
-		if (prev &&
-		    memblock_region_memory_end_pfn(prev) < memblock_region_memory_base_pfn(reg))
-			register_nosave_region(memblock_region_memory_end_pfn(prev),
-					       memblock_region_memory_base_pfn(reg));
-		prev = reg;
+	for_each_mem_pfn_range(i, MAX_NUMNODES, &spfn, &epfn, NULL) {
+		if (prev && prev < spfn)
+			register_nosave_region(prev, spfn);
+
+		prev = epfn;
 	}
+
 	return 0;
 }
 #else /* CONFIG_NEED_MULTIPLE_NODES */
diff --git a/arch/powerpc/mm/numa.c b/arch/powerpc/mm/numa.c
index 1f61fa2148b5..f4e20d8e6c02 100644
--- a/arch/powerpc/mm/numa.c
+++ b/arch/powerpc/mm/numa.c
@@ -804,17 +804,14 @@ static void __init setup_nonnuma(void)
 	unsigned long total_ram = memblock_phys_mem_size();
 	unsigned long start_pfn, end_pfn;
 	unsigned int nid = 0;
-	struct memblock_region *reg;
+	int i;
 
 	printk(KERN_DEBUG "Top of RAM: 0x%lx, Total RAM: 0x%lx\n",
 	       top_of_ram, total_ram);
 	printk(KERN_DEBUG "Memory hole size: %ldMB\n",
 	       (top_of_ram - total_ram) >> 20);
 
-	for_each_memblock(memory, reg) {
-		start_pfn = memblock_region_memory_base_pfn(reg);
-		end_pfn = memblock_region_memory_end_pfn(reg);
-
+	for_each_mem_pfn_range(i, MAX_NUMNODES, &start_pfn, &end_pfn, NULL) {
 		fake_numa_create_new_node(end_pfn, &nid);
 		memblock_set_node(PFN_PHYS(start_pfn),
 				  PFN_PHYS(end_pfn - start_pfn),